[petsc-users] AMG using ML : Advanced monitoring

[Karthik Duraisamy]

Dear all,

      I have been able to use AMG (using ML) for some of my problems and am looking to delve deeper into the workings of the algorithm to better understand how to use it for larger and more complex problems. Since my problems are hyperbolic and involve sharp gradients, I think there is a possibility that coarse level operators are not very stable in some problems. I see evidence of this because in many cases, I need to use lu or a very high k ilu(k) on coarser levels to keep the iterative solver from diverging.

    In this regard, I am wondering whether it is possible to obtain the coarse grid operators (or at the very least, the eigenstructure at these levels). Right now, I am doing the monitoring at the baseline level but I am looking for additional information.


Regards,
Karthik. 

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Karthik Duraisamy
Assistant Professor (Consulting)
Durand Building Rm 357
Dept of Aeronautics and Astronautics
Stanford University
Stanford CA 94305

Phone: 650-721-2835
Web:     www.stanford.edu/~dkarthik
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